Flavor-changing phenomenology in a $U(1)$ model

We investigate a family-nonuniversal Abelian extension of hypercharge, which significantly alters the phenomenological features of the standard model. Anomaly cancellation requires that the third quark family transforms differently from the first two quark families. Additionally, it acquires that three right-handed neutrinos are presented. This model generates naturally small neutrino masses and a $W$-boson mass deviation appropriate to recent measurements. Additionally, the model introduces flavor-changing neutral currents (FCNCs) of quarks coupled to the new gauge boson $Z'$ and new Higgs fields. These FCNCs significantly modify the neutral-meson mixing amplitudes and rare meson decays, which are studied in detail. We also address flavor changing processes in the charged lepton sector.